1. Field of The Invention
This invention relates to an improved cylinder-head cover gasket.
2. Description of The Prior Art
A cylinder-head cover gasket is disposed between a cylinder-block and a cylinder-head cover of an engine, so as to keep the air tightness therebetween. The conventional cylinder-head cover is produced of aluminium die casting and the like. A groove is formed at one side of the cover connecting with the cylinder-block, wherein a gasket is inserted. The section of the groove is U-shaped or square shaped.
In recent years, the cylinder-head cover made of aluminium die casting has been replaced with that made of pressed iron plates. Such cylinder-head cover of pressed iron plates is shown in FIG. 4, wherein a U-shaped groove 2a to support a gasket is defined with each surface of two plates 21, 22. The two plates 21, 22 are in contact with each other at the portion near of the end thereof. However, such U-shaped groove 2a for inserting the gasket 10 does not have a perfect U-shape or square cross section. Therefore the portion where the plates 21 and 22 are in contact with each other is wedge shaped to define the space 2b at the bottom of the groove.
As shown in FIG. 4, the conventional cylinder-head cover gasket is inserted to the groove 2a of the cylinder-head cover, then the cylinder-head cover 2 is fastened to the cylinder block tightly. In this case, the gasket 10 runs off to the wedge shaped space 2b, a condition not appreciated prior to this invention, so that the sealing may well be unsufficient because of the weak compression of the gasket 10 pressed between the cylinder-head cover 2 and the cylinder-block 3.